The association of the severity of anorectal malformations and intestinal malrotation.

Introduction: Intestinal malrotation is a known association of anorectal malformations (ARM). Exact incidence, prognosis and surgical implications related to ARM are unknown. The aim of this study was to identify relevant associations between ARM and the presence of malrotation.

Methods: Records of patients from two referral centers were retrospectively analyzed looking for malrotation associated to ARM and its management, as well as factors for functional prognosis.

Results: 40 patients out of 2572 with ARM (1.6%) were found to have malrotation. Females were more commonly affected, and severe malformations were more frequent (cloaca, covered cloacal exstrophy in females and rectoprostatic and rectobladder neck fistula in males). Factors significantly associated with malrotation included Müllerian or Wolffian duct anomalies (P<0.05), while fecal continence status, presence of constipation, and use of laxatives or enemas were not. Detecting and correcting malrotation early on or at the time of colostomy creation represented a protective factor against additional surgeries for bowel obstruction and volvulus (P<0.001). Removal of the appendix during malrotation treatment required constructing a neoappendicostomy using a cecal flap in 9 out of 14 patients needing antegrade enema administration.

Conclusions: Malrotation presence in patients with ARM has the same frequency as in the general population, but it is more common in severe malformations. Surgeons treating these patients should address the malrotation at the time of colostomy opening if detected. The appendix should be preserved for potential future use as an appendicostomy for antegrade administration of enemas.